This cross-sectional study was conducted from March 2021 through August 2021 among Bhutanese women who underwent colposcopy at JDWNRH. They were recruited by convenience sampling method. Married or sexually active women between the ages of 25 and 76 years with abnormal cytology result or women with gynecological complaints such as postcoital bleeding, intermenstrual bleeding, postmenopausal bleeding and unhealthy cervix who consented to undergo colposcopy and biopsy (either with punch biopsy or loop electro-surgical excisional procedure (LEEP) were included. Women with obvious cervical cancer, with history of LEEP, cold knife conization (CKC), and cryotherapy, treated for invasive cervical cancer with surgery, and/or chemoradiation therapy, and known pregnancy or puerperium were excluded.

The data on socio-demographic details of women were collected using an interviewer administered questionnaire after obtaining written informed consent. The data variables were age, place of current residence, educational status, marital status, occupation, age at first sexual intercourse, age at first childbirth, parity, and monthly income in Ngultrum.

Bhutan is located in the eastern Himalayas with a total population of 7,74,830 with female population consisting of 46.3% as of 2015 [12]. The health services are provided through a three-tiered structure: national and regional referral hospital at the tertiary level, general or district hospitals at secondary level, and basic health units (BHU), sub-posts and outreach clinics (ORCs) at the primary level.

Conventional Pap smear services are provided at all three levels of health care services in Bhutan. The specimens are taken by trained female health assistants or medical officers in the field, and transported to the laboratory in the standard method. Examination of cytology slides are done by the trained cyto-technicians. The suspicious slides are cross checked and confirmed by cyto-pathologists before issuing reports. Conventional Pap smear is done in the standard methods, and reported as per the 2014 Bethesda System for Reporting Cervical cytology including terminologies as- negative for intraepithelial lesion or malignancy (NILM), atypical squamous cells which is further subdivided into atypical squamous cells of undetermined significance (ASC- US) and atypical squamous cells, cannot exclude high-grade squamous intraepithelial lesion (ASC-H), low-grade squamous intraepithelial lesion (LSIL), high-grade squamous intraepithelial lesion (HSIL) and/or squamous cervical carcinoma (SCC).

The routine colposcopy services are provided by the Obstetrician-Gynaecologist at the comprehensive emergency obstetrics and neonatal care (EmONC) centres (Fig. 1), and during colposcopy camp services conducted in the secondary and primary health centres. Those cases with abnormal cytology reports are referred for colposcopy as per the national cervical cancer screening guideline, which is based on 2011 International Federation of Cervical Pathology and Colposcopy (IFCPC) [13]. As colposcopy clinics are conducted on fixed days (either once or twice a week), patient are routed based on prior appointment dates co-ordinated between the health workers in the field and colposcopy nurse.

Map of Bhutan showing the sites of comprehensive EmONC centers with pink asterisk (Used with permission from the Policy & Planning Division, Ministry of Health, Bhutan)

In this study, the colposcopy was performed by five Obstetrician-Gynaecologists, who had undergone some form of training abroad (Thailand). Two colposcopists with working experience as colposcopists for more than 10 years were categorized as “senior colposcopists”, and other three colposcopists with less than 10 years of working experience as colposcopists are categorized as “junior colposcopists”. The video colposcope (EDAN C3A) using 6–12 magnification was used. The standard steps described in the International Agency for Research on Cancer manual of colposcopy were followed [14], and the colposcopy findings were documented according to the International Federation for Cervical Pathology and Colposcopy nomenclature, and Swede score calculated [15, 16]. The colposcopy finding was described as normal, low-grade lesion (LGL), high grade lesion (HGL), and suspicious of invasion. Punch biopsy from the densest acetowhite areas near squamo-columnar junction (SCJ), and multiple punch biopsies in cases of normal colposcopy were taken using Kevorkian or Baby Tischler minibite biopsy forceps. Excisional treatment with LEEP was performed under total intravenous anaesthesia (TIVA) in the operation theatre complex of the hospital.

The cervical tissue specimens obtained from the patients were placed in 10% phosphate-buffered formalin and transported to the histology unit, Department of Pathology and Laboratory medicine, JDWNRH. The slides were constructed from 3 mm sections of formalin-fixed paraffin-embedded (FFPE) blocks and stained with Mayer’s Hematoxylin (HIMEDIA) and Eosin yellow (HIMEDIA) in the Sakura Tissue-Tek DRS 200 slide Stainer as per the standard operating protocol. The slides were then viewed under binocular light microscopy by two Pathologists, blinded to the colposcopy and the Pap results. The consensus report was provided by using the terminology of the WHO Classification of Female Genital Tumors, 5th edition [17].

Data were double entered, validated using EpiData (Version 3.1 for entry and version 2.2.2.183 for analysis, EpiData Association, Odense, Denmark), and analysed using STATA (version 13.1, StataCorp LP USA). The numerical variables were presented as mean and standard deviation, and the categorical variables were presented as frequency and percentage using descriptive commands. Sensitivity, specificity, and accuracy were used to assess the diagnostic performance of colposcopy to diagnose histologic CIN 2+. Chi-square test was used to analyze the relation between colposcopy and histologic results.

CIN 2+ (disease positive) included histopathologic diagnoses of CIN II, CIN III, CIS and invasive carcinoma, whereas CIN 2- (disease negative) included histopathologic diagnoses of normal, inflammation, and CIN I. For calculating performance of colposcopy, HGL and suspicious of invasion in the colposcopy were taken as colposcopy positive, whereas normal and LGL were taken as colposcopy negative.